@article{AMI_1998_25_a7,
     author = {Gyula Maksa},
     title = {Functions having quadratic differences in a given class},
     journal = {Annales mathematicae et informaticae},
     pages = {77--82},
     publisher = {mathdoc},
     volume = {25},
     year = {1998},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/AMI_1998_25_a7/}
}